Students are very familiar with writing and balancing chemical equations. This lesson will introduce the last type of chemical reaction known as double replacement. Once students have learned this last type, they will be able to look at any reaction and identify the type of reaction and predict the products of the reaction. Today the students will watch a demonstration of a double replacement reaction, practice some balancing, and complete a Chemical Reactions Lab that demonstrates four of the five types of reactions. Each mini lab they experience will require them to analyze the reaction, identify which type it is, and write the complete balanced equation. This is a great way for students to connect what they learned throughout the unit to real experiences.
Objectives
Students will…
Identify a reaction as either combination, decomposition, single replacement, combustion, or double replacement.
Compare/contrast double replacement with single replacement, combination, decomposition, and combustion.
Predict the products of combination, decomposition, single replacement, double replacement, or combustion.
Analyze the chemical reactions occurring in each part of the experiment and describe what is taking place
Materials
Chemical Reactions Lab (attached below)
Mini Lab 1: magnesium strips, bunsen burners, tongs, evaporating dishes
Mini Lab 2: test tubes, spatula, zinc(II) carbonate, bunser burner, wood splint
Mini Lab 3: test tubes, HCl, zinc strips, wooden splints
Mini Lab 4: CaCl2, Na2CO3, test tubes
Instruction
Opening (15 minutes)
Quiz- Predict the products of these reactions and balance the equation. Students will be given Activity Series (shown below)
Zinc + H2O -->
Copper(II) Sulfate + Aluminum -->
Chlorine + potassium iodide -->
Mercury + zinc nitrate -->
Do-Now: Take out homework. Open textbook to pg. 218 and read the section titled Double Replacement Reactions
Go over answers to homework worksheet. Worksheet will be displayed on the SmartBoard. I will have a one or two students come up and write in their answers to the HW. If other students did not get the same answers, or the answers are incorrect, we will review and correct the problems.
Ask students how their Adopt-a-Chem Rxn Projects are coming along. Any questions/concerns?
Explain today's focus: review single replacement, lecture about double-replacement, Chemical Reactions Lab
Middle (70 minutes)
Activity 1: 20 minutes
Practice some more Single Replacement Reactions
Have students write the reactions that occurred in each beaker from the Activity Series Lab
General Reaction: A + BC -> AC + B
Introduce Double-Replacement
What part of the compound was replaced in single-replacement reactions? (cation)
What parts of the ionic compounds will be replaced in double-replacement reactions? (cations)
What drives these reactions to occur? (formation of precipitate)
General Reaction: AB + CD -> AD + CB
Demo: 0.1M silver nitrate and 0.1M sodium chloride
Have students write balanced reaction and realize that at least one of the products is a solid, liquid, or gas (not aqueous)
Practice some examples
HCl + Fe(OH)3 --> FeCl3 + HOH(l)
Pb(NO3)2 + K2CrO4 --> PbCrO4(s) + KNO3
ZnS + H2SO4 --> H2(g) + ZnSO4
Ag2SO4 + AlCl3 --> AgCl(s) + Al2(SO4)3
Activity 2: 50 minutes
Chemical Reactions Lab (attached below)
students will complete all 4 Mini labs today. Students will work in groups of 2 or 3 and there will be two set-ups for each Mini Lab so that two groups can do the same mini lab simultaneously.
If groups finish early, they can begin to answer the questions for each Mini Lab and/or being to write up the Explanation.
Lesson #4: Classifying Chemical Reactions III
Summary
Students are very familiar with writing and balancing chemical equations. This lesson will introduce the last type of chemical reaction known as double replacement. Once students have learned this last type, they will be able to look at any reaction and identify the type of reaction and predict the products of the reaction. Today the students will watch a demonstration of a double replacement reaction, practice some balancing, and complete a Chemical Reactions Lab that demonstrates four of the five types of reactions. Each mini lab they experience will require them to analyze the reaction, identify which type it is, and write the complete balanced equation. This is a great way for students to connect what they learned throughout the unit to real experiences.Objectives
Students will…
Identify a reaction as either combination, decomposition, single replacement, combustion, or double replacement.Compare/contrast double replacement with single replacement, combination, decomposition, and combustion.
Predict the products of combination, decomposition, single replacement, double replacement, or combustion.
Analyze the chemical reactions occurring in each part of the experiment and describe what is taking place
Materials
Chemical Reactions Lab (attached below)Mini Lab 1: magnesium strips, bunsen burners, tongs, evaporating dishes
Mini Lab 2: test tubes, spatula, zinc(II) carbonate, bunser burner, wood splint
Mini Lab 3: test tubes, HCl, zinc strips, wooden splints
Mini Lab 4: CaCl2, Na2CO3, test tubes
Instruction
Opening (15 minutes)
Middle (70 minutes)
Activity 1: 20 minutes- Practice some more Single Replacement Reactions
- Have students write the reactions that occurred in each beaker from the Activity Series Lab
- General Reaction: A + BC -> AC + B
- Introduce Double-Replacement
- What part of the compound was replaced in single-replacement reactions? (cation)
- What parts of the ionic compounds will be replaced in double-replacement reactions? (cations)
- What drives these reactions to occur? (formation of precipitate)
- General Reaction: AB + CD -> AD + CB
- Demo: 0.1M silver nitrate and 0.1M sodium chloride
- Have students write balanced reaction and realize that at least one of the products is a solid, liquid, or gas (not aqueous)
- Practice some examples
- HCl + Fe(OH)3 --> FeCl3 + HOH(l)
- Pb(NO3)2 + K2CrO4 --> PbCrO4(s) + KNO3
- ZnS + H2SO4 --> H2(g) + ZnSO4
- Ag2SO4 + AlCl3 --> AgCl(s) + Al2(SO4)3
Activity 2: 50 minutesClosing (5 minutes)
Notes
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